Sending packets

A switch can be remotely commanded to send a packet. The packet can either be a packet buffered at the switch, in which case the bufferID is provided, or it can be specified explicitly by giving the packet data.

Constructors

PacketOutRecord
Fields bufferIDData :: !(Either BufferID ByteString) either a buffer ID or the data itself packetInPort :: !(Maybe PortID) the port at which the packet received, for the purposes of processing this command packetActions :: !ActionSequence actions to apply to the packet

Instances

Eq PacketOut
Show PacketOut

bufferedPacketOut :: BufferID -> Maybe PortID -> ActionSequence -> PacketOut Source

Constructs a PacketOut value for a packet buffered at a switch.

unbufferedPacketOut :: ByteString -> Maybe PortID -> ActionSequence -> PacketOut Source

Constructs a PacketOut value for an unbuffered packet, including the packet data.

receivedPacketOut :: PacketInfo -> ActionSequence -> PacketOut Source

Constructs a PacketOut value that processes the packet referred to by the PacketInfo value according to the specified actions.

type BufferID = Word32 Source

A switch may buffer a packet that it receives. When it does so, the packet is assigned a bufferID which can be used to refer to that packet.

Packets not handled by a switch

data PacketInfo Source

A switch receives packets on its ports. If the packet matches some flow rules, the highest priority rule is executed. If no flow rule matches, the packet is sent to the controller. When packet is sent to the controller, the switch sends a message containing the following information.

Constructors

PacketInfo
Fields bufferID :: !(Maybe BufferID) buffer ID if packet buffered packetLength :: !NumBytes full length of frame receivedOnPort :: !PortID port on which frame was received reasonSent :: !PacketInReason reason packet is being sent packetData :: !ByteString ethernet frame, includes full packet only if no buffer ID enclosedFrame :: !(Either String EthernetFrame) result of parsing packetData field.

Instances

Eq PacketInfo
Show PacketInfo

data PacketInReason Source

A PacketInfo message includes the reason that the message was sent, namely either there was no match, or there was a match, and that match's actions included a Sent-To-Controller action.

Constructors

NotMatched
ExplicitSend

Instances

Enum PacketInReason
Eq PacketInReason
Ord PacketInReason
Read PacketInReason
Show PacketInReason

type NumBytes = Int Source

The number of bytes in a packet.

bufferedAtSwitch :: PacketInfo -> Bool Source